P.O.lari.S blown 800's again

[melb-09-rmk-assault]

wat elevations r u guys rideing at. i have hear dof so many 800s screwing up. i ride at around 8000 to 10000 ft in the rockies and i have a snow check assault and have the new reflash and i havent had anything wrong and i ride the **** out of mine and always on the throttle, another guy n our group has a 08 d8 and he hasnt had anything wrong with his and i have talked to the dealer i get my stuff from n glennwood colorado and he has had only a few problems with the 800s and it was mainly just snow getting n the intake and thats it. so i feel sorry for u guys alot and i hope nothen happens to mine.

 

[auggie11]

09 D8 with around 610 miles and riding at around 8,000 to 10,000. A buddy had also just locked his up the weekend before mine. His was a crank bearing. And as for mine like others had said I believe the problems were there before I had gotten the reflash.. But anyway recieved the reflash on a friday and locked her up on friday night after about 6 miles. Proper warm up as I always allowed it to warm up to about 100.. No constant speed down the trail at time. Locked up on PTO side. Scuffing all the way around. Hardly any oil at all on PTO side. And dealer has no idea and says polaris is saying they are not seeing this as a common problem... So they are fixing it and we'll see how it goes... Came from cat to polaris.. absolutely love the sled. Just hope to have the same reliability I had wiht the previous 3 cats i'd owned.

 

[1Mike900]

I have a funny feeling it is the single ringed piston not transferring enough heat to the cylinders? Has anyone taken a piston to wall clearance check and see if it is not too tight to begin with on some sleds? Snow ingestion should only be a problem in the deep, But down a trail no!

Mike

 

[Cardiac Kid]

Yes, but I doubt that is your problem. You wouldn't see that with any stock or most aftermarket pipes today. And if you did it would likely only occur at near wide open and on a longer pull. When I was younger we ran tight pipes on short drag races because it builds heat fast and makes horse power.

Think not enough fuel or too much air. A couple of other things I would have checked if this was happening to me is: TPS as Ron said, and Bad exhaust temp probe as these two sensors will effect fuel delivery. Also low fuel pressure, or dirty fuel filter. All of these would affect both cylinders so you should be seeing a lean condition on the other cylinder that did not die. A bad injector or plugged injector would affect only one cylinder and depending on which injector it was, only the low high flow signal (two injectors per cylinder one for high flow and one for low flow). Make sure all 4 injectors are plugged in, had a friend loose one of these motors because one of the electrical connectors was loose on his injector. That got him a new motor. Buy a simple ethanol fuel checker. You can get one at an auto parts store. It just a glass vile and you put a touch of water and then the gas and shake, very cheep but they work great. If you are seeing greater than 10% ethanol in the fuel you buy, this could be the problem.
A bad throttle body boot with a crack in it will create a lean condition. A bad crank seal will do the same.
The problem with the new sleds is we tend to forget sometimes they are still nothing more than an air pump and every thing we have ever learned still applies, just the inputs changed.

 

[Cardiac Kid]

Some just score ther pistons and others will actually put a hole in the piston or just melt it. The problem with some of the engines is they are half gone when they get the reflash. Other problem is we don't really know what the afr's are with the new reflash. Jim at Dynotech is supposed to get those numbers so we will know. Most guys that are blowing up have done some part throttle riding and thats were the problem is.

Yes I am running a pwrcmdr and have not had any problems. Yes it cost a few bucks but I have also paid for a pipe,reeds and few other things. It is just one more piece to make my sled run better than the next guys.

Sounds like a mix. I see there is another post with scoring all the way around the piston like oil and then some pistons with holes in the top-- detonation or pre-ignition.
Well that tells me that it isn't just one problem so that’s kind of good, it just mean that each case has to be treated on its own, which makes it tough for the shop guy that isn't riding the sled every day.
I think some of the issues here is Polaris didn't do a good job with the fuel map and now everything is assumed to be a computer problem so we look for a common problem that is the fault of the computer. The old 800's ran great with way more fuel than they needed and thats the way most of my friend jetted theirs. Now things are a little tighter and there isn't a much room for change and a tank of dirty fuel or bad gas may have more to do with it than we think. Three and four sleds in the same area on the same weekend burning down and in other areas no sled having problems. This just screams bad fuel being distributed in that area but it could also be something else common to that area like riding condition combined with air temp and altitude. I hope the guys having repeat problem fine the cause because it sucks to have a sled in the shop.

 

[highpressure]

.................for 2010 we'll all be getting the new L.E.A.N.F.I.R.E engine in our DRAGGIN's.

 

[penguinpoo]

They can't get much leaner than they are and resemble a running engine, I am adding 25% fuel in some parts of my map(not reflashed and slp pipe) and that is just to get it out of the lean stumbles.

 

[JDen]

I noticed on my 08 D8 when I took the airbox off for another reason that there was daylight going into the airbox all the way around the seem in the middle, made it run very lean, took it apart, sealed it up, put back together and seems to not be running so lean....just my 2 cents...

 

[EricW]

I pulled my motor last week to get ready for a turbo. I had a scuff like the ones shown on the mag/exhaust side. I also saw a ton of belt dust in my throttle bodys. I think sealing up the air box and plenum is a good thing to do.

Since the rebuild I have noticed the lean spot that XC70016 noted between 6000 & 7000 RPM. If I were to just hold the throttle constant on the trail anywhere above 6500 I can see the egt's go in the upper 1200's to over 1300 at times. I have been just riding around it and flipping the throttle as it runs well with my current numbers. I might try to fatten it up a bit in that range and see what happens.

Critical or not, I am more determined to do a good heat sink warm up now, we'll see how long she lasts. Good info. EW

 

[thefullmonte]

I have a funny feeling it is the single ringed piston not transferring enough heat to the cylinders? Has anyone taken a piston to wall clearance check and see if it is not too tight to begin with on some sleds? Snow ingestion should only be a problem in the deep, But down a trail no!

Mike

These motors have more piston to cylinder clearance than any motor I've ever had apart. Forgive me, I don't have the specs in front of me. Turning the motor over by hand with the head off, you can see the piston tipping inside the cylinder! On a non scored piston you will see the piston coating gone on the top of the exhaust side and the skirt of the intake side only. (I may have that backwards ) but you get the idea. At TDC you can move the piston back and forth far enough to where the ring is almost out of the groove.
All I can think is that the materials used in the pistons is very inferior. And requires a massive expansion when heated to bring the tolerances closer or we would see all kinds of skirt failures by now.
I'm patiently waiting for an aftermarket piston option with much closer tolerances.
As Ron stated it is crucial that the TPS is in adjustment.

 

[sled_guy]

I noticed on my 08 D8 when I took the airbox off for another reason that there was daylight going into the airbox all the way around the seem in the middle, made it run very lean, took it apart, sealed it up, put back together and seems to not be running so lean....just my 2 cents...

That should have made it run rich... sucking warm under hood air in.

sled_guy

 

[duc848]

I am going to chime in here even though I dont own one of these sleds and have not owned a sled since 04. I planning on buying one as soon as I sell a Ducati that I have. I have worked in the snowmobile/motorcycle industry for around 11 years now lately in the cycle side of things. I have a few questions: Is it a manual TPS setting meaning you have to manually set or does the diagnostic tool or laptop reset it while hooked up? I am assuming that the map in the ECU is set more for EPA than anything else. That leads to my next question: How can you put a pipe, can, and airbox mod on one of these and not do anything and just ride it? I call BS on that one. If you put a full exhaust system, airbox mod of any kind to a bike you need an aftermarket ECU or a Power Commander. The bike simply will run way too lean and cause engine damage over time. I have seen it time and time again. I am a little confused about the elevation thing as well. The ECU should compensate for at least that if they have the correct sensor. My take is that the mapping is way too lean, the TPS is incorrectly set, the oil pump is not calibrated. if it is a manual reset for the TPS they do go out of adjustment as I have seen that as well on almost everything that has a manual adjustment.

If I were to buy one of these it woud have exhaust, airbox mod, as well as a PCIII before I even rode it.

 

[duc848]

I found the TPS reset thread. It is the same as an older Ducati which do go out of adjustment. This is very critical as this is what the whole system is based off of. I know that the throttle plates need to be closed not at idle.

 

[Mopar21277]

Have you guys run any aftermarket coating on the pistons, like Swaintech's polymoly on the skirts and ceramic coated domes? What about running say a 100:1 pre-mix in the fuel to add a little extra oil to offset that damn ethanol?

I was pumped about trying to get a D8 shorty, but now I wouldn't touch it; I'll stick with the carbs. I'm going to inquire to IndyDan if he is building any 800 small blocks using the 600 HO carbie as the base. Bikeman is doing an 800 kit for the 600 race engine, I wonder if the 600R/800 CFI crank can be used in the 600HO cases...

 

[youngent]

I have to agree.Did the people that have problems run fuel line antifreeze?EFI does not like water or ice in the fuel. I have EGT on my sled 08 D8 does seem lean at 6000
but so have all my previous sleds have to vary the throttle. My sled has a turbo installed this didn't seem to change the lean spot, think it has to do with the injectors switching for low rpm to high rpm. Hope this helps.

 

[crf118r]

We've done a few of the new 800's and they all look the same. There is always excessive exhaust side scoring and the intake side has about an inch of scuffing at the very bottom of the skirt. Here's a couple pics.

So am I crazy or should the piston NEVER touch the cylinder walls, and if not that means you should never see any signs of scoring, even if ever so slightly on the piston looking in from the exhaust valves? I feel like I'm being too cautious now that I'm on my second motor. I checked after the 3rd ride and I have a lighter version of this on the mag side mainly and an even lighter amount on the clutch side, But the signs seem to be evident. I think my dealer (who is great btw) thinks I'm psychotic!

 

[steveo10]

my friend just cant get past KM11 on the trail... now he just burnt down his pooplaris dealership

 

[GMCRMK]

my friend just cant get past KM11 on the trail... now he just burnt down his pooplaris dealership

Muligan. Try again.

 

[crf118r]

English dude.

 

[klj]

So am I crazy or should the piston NEVER touch the cylinder walls, and if not that means you should never see any signs of scoring, even if ever so slightly on the piston looking in from the exhaust valves? I feel like I'm being too cautious now that I'm on my second motor. I checked after the 3rd ride and I have a lighter version of this on the mag side mainly and an even lighter amount on the clutch side, But the signs seem to be evident. I think my dealer (who is great btw) thinks I'm psychotic!

You are NOT crazy. There should be no scoring. When Polaris brings out the final fix (sometime between now and fall) you should be getting new pistons and monoblock along with the new map even if the final fix is only new mapping. All of this should be under warranty.